Lecture 2a

Question 1

Study of symptoms and signs that characterize a plant ailment to provide accurate diagnosis

Answer 1

Symptomatology

Question 2

2 Types of Symptoms based on location

Answer 2

1. Systemic

2. Localized

Question 3

Appears on specific plant part

Answer 3

Localized symptoms

Question 4

Manifested by the entire plant although the cause may not be necessarily present over the entire body or individual

Answer 4

Systemic symptoms

Question 4

Manifested by the entire plant although the cause may not be necessarily present over the entire body or individual

Answer 4

Systemic symptoms

Question 5

Manifestations of disease conditions

Answer 5

Symptoms

Question 6

3 Types of Morphological Symptoms

Answer 6

1. Necrotic
2. Atrophic or Hypoplastic
3. Hypertrophic or Hyperplastic

Question 7

Symptoms resulting from a decrease in cell division; inhibition of growth; decrease the production of substances or underdevelopment of plant organs

Answer 7

Atrophic or Hypoplastic Symptoms

Question 8

Symptoms resulting from over-multiplication of cells, overproduction of substances or pigments, and over-development of plant organs

Answer 8

Hypertrophic or Hyperplastic Symptoms

Question 9

Visible symptoms resulting from destruction or death of cells or tissues

Answer 9

Necrotic Symptoms

Question 10

3 Necrotic Symptoms

Answer 10

1. Spot, Blotch, Shot hole, Anthracnose, Blight, Scorch, Yellowing, Wilting
2. Rot or decay, Canker, Scald, Dieback, Damping-off
3. Bleeding – slime flux, resinosis, gummosis

Question 11

elongated spots on monocot leaves

Answer 11

Blotch

Question 12

Black or purple coalesced spots or lesions on the leaves or fruits

Answer 12

Anthracnose

Question 13

Circular holes on the leaves as a result of removal or dropping out of diseased/infected tissues

Answer 13

Shot hole

Question 14

discolored circular or angular lesions on leaves or fruits

Answer 14

Spot

Question 15

Death or browning of foliage due to pathogens

Answer 15

Blight

Question 16

Death or browning of foliage or “burning” of leaf margins due to physical factors.

Answer 16

Scorch

Question 17

Flaccid condition of leaves/ shoots caused by lack of water or loss of turgidity.

Answer 17

Wilting

Question 18

Normally green tissues of the leaves turn yellow due to the destruction of chloroplasts.

Answer 18

Yellowing

Question 19

Give an example of Wilting

Answer 19

Fusarium wilt/Panama Disease of Banana and Abaca

Question 20

What organ does Fusarium oxysporum f.sp. cubense attack?

Answer 20

Pericycle

Question 21

Dead tissue in an advanced stage of

decomposition

Answer 21

Rot or decay

Question 22

Rot may appear in ____ as well as in ___ parts of a plant.

Answer 22

woody organs, fleshy parts

Question 23

Localized, sharply demarked lesions usually sunken or cracked, on the stem bark.

Answer 23

Canker

Question 24

Give an example of a causal agent of canker

Answer 24

Erythricium salmonicolor

Question 25

Blanching of the epidermal tissues that gradually turn pale brown or darker, usually due to physical factors like intense sunlight.

Answer 25

Scald

Question 26

Progressive death or browning of shoots, branches and foliage, generally starting at the tip.

Answer 26

Die back

Question 27

Rapid rotting of seeds before they emerge from the ground (pre-emergence) or the rapid rotting of the base of seedlings so that they fall over or rotting of the shoot (post-emergence).

Answer 27

Damping-off

Question 28

Continuous oozing of sap from wounds or injuries

Answer 28

Bleeding

Question 29

Bleeding accompanied by fermentation, usually with foul odor

Answer 29

Slime flux

Question 30

Bleeding of gummy substance

Answer 30

Gummosis

Question 31

Bleeding on coniferous trees

Answer 31

Resinosis

Question 32

3 Atrophic Symptoms

Answer 32

1. Chlorosis, Albication, Mosaic 2. Dwarfing, Suppression 3. Rosetting, Etiolation, Witches' broom

Question 33

Yellowing of some parts of leaves due to partial suppression of chlorophyll formation in the leaves.

Answer 33

Chlorosis

Question 34

Viral diseases of plants characterized by intermingled patches of normal and light green or yellowish color.

Answer 34

Mosaic

Question 35

Give an example of Mosaic Disease

Answer 35

Papaya ringspot virus

Question 36

Complete suppression of chlorophyll formation in the leaves, resulting in very light yellow or beige color.

Answer 36

Albication

Question 37

Below normal size of the plants or some of its organs such as in bonsai plants.

Answer 37

Dwarfing

Question 38

Failure of certain organs to develop at points where they normally grow such as fruit or flower abortion.

Answer 38

Suppression

Question 39

Crowding of foliage resembling rose petals (rosette) due to shortening of the internodes.

Answer 39

Rosetting

Question 40

Excessive spindiness of the plant/shoot elongation and chlorosis due to poor light conditions

Answer 40

Etiolation

Question 41

Circular swelling on the leaf, stem or root of plant

Answer 41

Gall

Question 42

2 Examples of Gall Disease

Answer 42

1. Gall rust of Falcata | 2. Crown gall

Question 43

Causal agent of gall rust

Answer 43

Uromycladium falcatarium

Question 44

Causal agent of Crown gall

Answer 44

Agrobacterium tumefaciens

Question 45

Uncontrolled overgrowth of plant tissue(s)

Answer 45

Tumor

Question 46

New plant tissue growing over a wound or an injury in an attempt to heal it.

Answer 46

Callus

Question 47

Swelling or bulging of bark beyond girdling wounds or cankers due to excessive food accumulation from leaves coming down the phloem and being stopped at the lesion.

Answer 47

Sarcody

Question 48

Overproduction of anthocyanin pigment on the leaves, especially in grasses.

Answer 48

Anthocyanescence

Question 49

Bending of leaf or shoot due to overgrowth on one side of the affected organ.

Answer 49

Curling

Question 50

Downward curling of leaf blade as a result of more rapid cell growth on the upper side of the petiole

Answer 50

Epinasty

Question 51

Premature falling of the leaves

Answer 51

Abscission or defoliation

Question 52

Local swelling of any plant part, usually woody root, stem or branch resulting from meristematic stimulation by the pathogen.

Answer 52

Tumefaction

Question 53

3 Forms of tumefaction

Answer 53

1. Burls 2. Warts 3. Knots

Question 54

Develop from twig bud cells that continue to multiply without differentiation

Answer 54

Burls

Question 55

Flattening of organs such as flowers, roots and stems.

Answer 55

Fasciation

Question 56

Clustering of branches about some common point on the plant.

Answer 56

Fasciculation/Brooming

Question 57

Fasciculation arises from the development of ____ buds

Answer 57

Adventitious

Question 58

Evidences of pathogen on diseased plant

Answer 58

Signs

Question 59

3 Types of Signs

Answer 59

1. Vegetative 2. Reproductive 3. Others: bacterial droplets or bleeding

Question 60

4 vegetative signs

Answer 60

1. Hyphae 2. Mycelium 3. Rhizomorph 4. Sclerotial body

Question 61

Group of hyphae forming a cottony visible mass

Answer 61

Mycelium

Question 62

Root-like strand of a fungus, used for nutrient absorption

Answer 62

Rhizomorph

Question 63

Microscopic filamentous vegetative strands of fungus

Answer 63

Hyphae

Question 64

Hardened mass of hyphae, usually resistant to adverse conditions

Answer 64

Sclerotial body

Question 65

2 Reproductive Signs

Answer 65

1. Spore | 2. Fruiting body

Question 66

Basic reproductive unit of fungus

Answer 66

Spore

Question 67

Structure containing asexual or sexual spores

Answer 67

Fruiting body

Question 68

Example of fruiting body

Answer 68

Ganoderma

Question 69

Example of fungal spores

Answer 69

Colletotrichum